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EXPLORING BEAVER HABITAT AND DISTRIBUTION WITH GOOGLE
EARTH:

EXCEPTIONAL BEAVER HABITAT ON THE SLOPES OF THE PASQUIA
HILLS, SASKATCHEWAN

Beavers are interesting to study with Google Earth since their "foot print" is clearly visible on the high resolution and somewhat recognizable on low resolution
images. The images below (left) gives the distribution of beaver (Castor
Canadensis) in North America. The image on the right give the locations
which I have studied with Google Earth, mostly high resolution imagery
to locate, measure and classify beaver dams. The longest beaver dam found
by me to date is about 600 meters in length. In some cases two dams (each
with its own lodge) connect and I have observed lengths of over 900 meters.

The slopes of the Pasquia Hills area in Northern Saskatchewan have some of
the most impressive beaver habitat and beaver densities I have seen so
far. While 10 -15 beaver dams in a stretch of 1000 meters of streambed
are not uncommon, it is is exceptional to find 15-20 beaver dams distributed
evenly in a square kilometer of "wetland". Not all dams have lodges with
them. As each lodge seems to have an average of about 5.2 beavers, the
average population density in some of the wetlands on the slopes
surrounding the Pasquia Hills could well be over 50-100 beavers per
Km2!!

Beaver dam locations reviewed with Google Earth

Beaver Distribution in North America (from Hinterland Who's Who)

Most of the areas visited are linked to exploring the northern limit for beaver.
Most of the sites on this GE image are in the low subarctic or
high boreal wetland regions.

Beaver Habitat Pasquia Hills Plateau and Slopes

The Pasquia Hills from a prominent landscape feature in the Boreal Plains Ecoregion.
They tower over the surrounding lowlands. The plateau itself
is flat plain ( dark blue and green on this NASA World Wind
1990 Pseudo Color image) with typical ground moraine land forms
shaped by the moving
ice
sheet (fluted
land forms -see yellow arrows and knoll and kettle topography
typical of a dead ice moriane in the northern are. The vegetation
and abundant wetlands on the plateau is typical of the mid-
boreal ecoregion: Black Sruce -feathermoss and jack Pine fire
regeneration on the well drained sites. The wetlands are typical
fens and bogs with tamarack and stunted black spruce. The slopes
in vivid green reflect the abundance of poplar species and
white birch in more disturbed areas. Many prominent beach lines
of the former Glacial Lake Agassiz are visible on this image
(LA marked with blue arrows). They were formed while the Glacial
lake receded. They slow down drainage and enhance potential
beaver habitat.

Highest Polpulation Density of Beaver in Canada?. Beaver occur in high densities
on the slopes. They are marked with a large asterix, showing
remarkable
concentration
areas,
and
a smaller
asterix
for the smaller and more steeply sloping areas.

The dotted lines show very high concentrations of beaver dams. In some areas
as high as 15-20 beaver dams per km2. The image below one of
these
areas close to the Cree First Nation community of Pakwaw Lake.

Black Spruce and Tamarack Bogs and Wetlands
are typical for this area (BB). Beach lines are prominent parts
of the landscape . The roads (as visible on the image) tend
to make use of the natural occurrence of these gravel beds.
Where the natural drainage breaks through these beds Beaver
have taken over the management of water.

High beaver Concentration Area ner Pakwaw Lake: Example of High Density - Low
Slope area

This Digital Globe Image shows one of the highest beaver dams concentrations
in Canada (in the world?) Over 20 dams and lodges per Km2.
The beaver lodges are clearly visible as light dots (7-8 meters
in size) in the inundated areas. It is typical to find high
densities of dams in streams (10 - 25 dams per linear Km) but
is is rather unusual to find them evenly spread out over a
wetland like this. This image shows a portion of a large beaver
community near Pakwaw Lake (see below)

Canada's Beaver Capital? The Shoal Lake Band of the Cree Nation is
located along Provincial Highway #55. The community is a short
drive from Nipawin, and Carrot River
Saskatchewan, and is 1479 hectares in size. The population
is 631, with an estimated 489 residing on-reserve. What is
so remarkable is the large beaver community located nearby. More information....

Beaver dams in slightly sloping wetland streams. The stream on the left has no
or very little beaver activity. Beavers have preferred to work
with
the slower
and
more consitent
surface
and ground
waterflow in the wetlands to the right of the image. Here the
specific sream flows are contriolled by regularly spaced beaver
dams with a spacing between them varying from 50-200 meters.

Low Resolution Satellite Image Recognition: The beaver dam areas are visible
on the low resolution Satellite images as well. The place mark
show
a
high concentration
of
dams od
substantiual
size. One perhaps close to 560 meters in length. The bottom
right hand corner shows also a series of lake like features which
are managed by beavers but reflect in size and distribution the
orientation of former glacial lake beach lines and possibly some
land slides on the steeper slopes.

The Pasquia Plateau has significant wetland areas as shown on the left high resolution
image. About 90% of this area would be considered a wetland (fen).
Beavers have focussed their attention on a small creek with
higher trees nearby as food supply. Flow is from the right to
the left.

Pasquia Plateau: Typical image of the better drained upland area with Black Spruce
as the dominat vegetation type. Dams reflect the direction
of the waterflow from top right to bottom left. The widest
dam is about 450 meters (bottom marker). The light green coloured
wetland, a Tamarack fen, with some areas of balck spruce and
bog type features shows little beaver activity.